Method and apparatus for treating materials



Feb; 24, 1942.

,A METHOD AND APPARATUS FOR TREAT-ING MATERIALS Filed Sept. r5, 1940INV/NTOR Herk?? (i. 707e Patented Feb-V24, 1942 Y Herbert G. vere,.reeksen Heights, N. Y., assigner to American Seal-Kap Corporation ofDelaware, Wilmington, Del., a corporation of Dela- WIPO Appuesuenseptember s, i940, serial No. 355,441

(el. sli- 55) 3 Claims.

This invention relates to a method and apparatus for treating materialsand more particularly to a method and apparatus for cooling waxtreatedpaper blanks.

This invention isan improvement onP the process for treating paperblanks to condition the same for the formation of cover-all milk bottle.caps as described in the `Baum Patent 1,668,349.

In that process the blanks are wax-treated or impregnated, stacked, andstored for seasoning or tempering to condition the same for a severeforming operation. It has been found, however,

that in order to obtain uniform impregnation and to prevent the blanksfrom sticking together Awhen stacked, the surface of the wax-treatedblanks must be cooled at least to a temperature below themelting pointof the wax before stacking. One method of accomplishing this is toholdthe blanks on a conveyor for a sufficiently long time toallow the blanksto.become cooled to the desired point. 'I'his method, however, isunsatisfactory from a quantity production standpoint due to theexcessive space which would be required for long conveyors of the typeabove indicated.

An object of the invention is to provide a novel and improved means forcooling the wax-treated blanks prior to stacking.

Another object is to provide a cooling system which is applicable to thetreatment and processing of various materials.

Another object is tofprovide means for quickly and eiiiciently coolingblanks of the type above indicated, which requires onlya minimum. tamount of'plant space and equipment.

Various other objects and advantagesV will be apparent as thenature ofthe invention is more fully disclosed.

In accordance with the present invention, I have found that the blanksmay be quickly and uniformly cooled by spraying thereon aesmall quantityof a readily vaporizable liquid such as water and utilizing the heat ofthe blanks to vaporize the liquid. The latent heat of vaporization 'ofthe vliquid thus serves to extract heat from the blanks and therebyrapidly cools the same to the desired point. A minimum amount of liquidis4 used and the major part of the liquid is immediately evaporated andremoved from the blanks so as not to interfere with the subsequentoperations. A predetermined amount of moisture may, if desired, beallowed to remain on the blanks for conditioning the same for thesubsequent forming operations.

air from contact with the blanks and facilitates the vaporization of thewater.v

'I he surfaces of the blanks are thus cooled quickly to a point suchthat the wax film thereon becomes solidified. The body of the blank,however, remains hot and when the blanks are stacked the stored heatserves to gradually soften the wax and causes the same to be drawn intothe fibres for impregnating the blanks. The wax is not softened on thesurface, however, to such an extent that the wax tends to flowand causeuneven impregnation or to cause the blanks to stick together. Thislatter feature is of particular importance when the wax containsadhesive mato be characteristic of this invention are pointed out moreparticularly inthe claims appended representation of a wax treatingprocess embodyhereto, the invention itself,'as to its objects andadvantages and the manner of its operation, may be better understood byreferring to the following description, taken in connection with theaccompanying drawing in which'a specific embodiment thereof has been setforth for purposes of illustration.

In the drawing, the figure is a' diagrammatic ing the present invention.

In the following description and in the claims certain specific termsare used for convenience in referring to various details of theinvention. It is to be understood, however, that these terms are to begiven as broad an interpretation as the state of the art will permit.

Referring to the drawing more in detail wherein the invention is appliedto the treatment of a paper blank to be used for the formation of milkbottle caps in accordance with the process set forth in the Baum Patent1,668,349 above referred to, the material is shown in the form of a webIt which is supplieddfrom a roll Il. The web I0 is fed from the roll I lby suitable means not shown, to a punch or die I2 wherein the desiredblanks are punched therefrom, the used web being taken up in a roll I 3.The blanks I4 which are punched from the web I0 by the die' I2 arepassed by conveyors- Il and I6 through wax baths I1 and- I) respectivelyin tanks I9 and. The wax may I In one embodiment the wax-treated blanksare be maintained in a molten condition by any suitable heatingmeans notshown. Upper webs 2l and 22 may be provided to hold the blanks inposition in the bath during the wax treatment.

The blanks Il, after removal from the tank 20, are passed betweensqueeze rollers 25 which are j so adjusted as to remove theexcess waxcoating from the surface of the blanks and to discharge the blanks ontoa conveyor 2B with a predetermined wax nlm on the surface thereof.

vaporization is thus utilized for cooling the sur-v face of the blanksas above indicated. After clncally applied to the treatment of paperblank to be used for the formation of cover-all milk bottle caps, it isto be understood that the cooling system is also applicable tovariousother processes wherein it is desired to quickly coolwebs or blanks. Theinvention is only to be restricted in accordance with the scope of theappended passage under the hood 28, the blanksare passed under a dryinghood 32 which is supplied with a current of cold air by a fan or blower33 actu-f ated by a motor 34.

After these blanks have thus been cooled, they are discharged into astacking device 354 wherein they are stacked and may be removed tostorage or to suitable cap forming mechanism as may be desired.

' In the operation of this system it is to be understood that water maybe applied to the blanks prior to wax treatment if desired as set forthin the Baum patent above mentioned. It is also to be understood that thequantity of liquid s'upplied by the nozzles 29 andthe time of treatmentvunder the hood 32 are so controlled that all of the water supplied totheblanks is evaporated from the surface thereof or so that a portionremains thereon for conditioning the blanks as may be desired.

It has been found that an extremely small quantity of water issufficient for the above purpose and that, when operated as aboveindicated, the evaporation of the water rapidly cools the surface of theblank to a point such that the wax becomes hardened and subsequent nowof the wax which would produce uneven impregnation is avoided. The bodyof the blank, however, is not immediately cooled and the heat storedtherein is sufficient to cause the wax to become absorbed into the nbresof the blank itself, as set forth in detail in the above mentioned Baumpatent.

The quantity of cooling liquid is not sumcient to cool the blanks byheat absorption but is so l regulated that the latent heat ofvaporization of a small quantity of readily vaporizable liquid isutilized for the purpose. -While waterhas been claims.

What is claimed is:

1. An apparatus for treating paper blanks, comprising a reservoircontaining a molten wax bath, conveyor means for passing said blanksthrough Asaid bath, a cooling zone, conveyor means passing thewax-treated blanks from said reservoir through said cooling zone, meansspraying a vaporizable liquid onto the blanks in said cooling zone in aquantity such that the heat of the blanks vaporizes at least the majorpart of g said liquid and a drying zone including means to supply acurrent of cold air over said blanks for removing said vapor, vsaidconveyor means carrying said blanks from said cooling zone through saidlast zone.

2. Thevprocess for preparing blanks for the formation of formed articlessuch as milk bottle caps, which comprises passing said blanks through awax bath to impregnate the fibers thereof with said wax and to form asurface film of wax thereon, removing Asaidblanks from said' bath,spraying ontothe surface of said blanks a vaporizable liquid in aquantity such that the heat of the blanks vaporizes at least a majorpart of said liquid, passing said blanks through a drying zone and insaid drying zone rapidly removing the vapor` laden air from-contact withsaid blanks under conditions to utilize the heat of vaporization of saidliquid as a cooling agent to cool rapidly the surface of said blanks toa point such that the Wax nlm thereon solidines.

3. The process for preparing blanks for the formation of formed articlessuch as milk bottle caps, which comprises passing said blanks through awax bath to impregnate the fibers thereof with said wax and to form asurface nlm of, wax thereon, removing said blanks from said bath,spraying onto the surface of said blanks a vaporizable liquid inaquantity such that the heat of the blanks vaporizesat least a majorpart of said liquid. passing said blanks through a drying zone and insaid drying zone rapidly removing the vapor laden air from contact withi said blanks under conditions to utilize the heat found satisfactory,various other vaporizable liquids may be used if desired.

While the invention has been shown as speof vaporization of'saidliquidas a cooling agent to cool rapidly the surface of lsaid blanks to apoint such that'the wax fllm thereon solidiiies while the body of theblank retains stored heat, and stacking the blanks for a sufficient timeto .allow the stored heat-to soften and draw the surface nlm of wax intothe .nbers for impregnating the same;

HERBERT G. VORE.

